Melatonin
Melatonin is a pineal hormone that regulates circadian rhythm. Trials have examined it mainly for sleep onset and jet lag.
- Evidence
- AStrong evidence
- Studied dose
- 0.3-3mg
- Safety score
- Verified references
- 1 study
How it is thought to work
The pineal gland releases melatonin in darkness. It binds MT1 and MT2 receptors in the suprachiasmatic nucleus and can advance, delay or stabilise the circadian rhythm depending on timing. Antioxidant actions are reported in animal studies.
Where to buy Melatonin
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| Vendor | Product | Size | Price | Per unit | Buy |
|---|---|---|---|---|---|
| Amazon |  Amazon Basics Melatonin 5mg, 120 Gummies (2 per Serving)... | - | On Amazon | - | Check price on Amazon Ad |
| iHerb | Nutricost, Melatonin, 10 mg, 240 Capsules | - | about $12.95 at iHerb (as of 24 September 2026) | - | Shop Ad |
| iHerb | Pure Encapsulations, Melatonin , 20 mg, 60 Capsules | - | about $39.00 at iHerb (as of 24 September 2026) | - | Shop Ad |
| iHerb | NOW Foods, Melatonin, 90 Lozenges | - | about $4.88 at iHerb (as of 24 September 2026) | - | Shop Ad |
What the studies found
| Claimed benefit | Grade | Basis |
|---|---|---|
| Sleep onset | A | Graded A, but no verified study is cited for this claim yet.Multiple meta-analyses. |
| Jet lag | A | Graded A, but no verified study is cited for this claim yet.Source being re-verified |
| Antioxidant | B | Mechanism + animal. |
Each benefit is graded on its own; a substance can have strong evidence for one effect and little for another. What the grades mean.
Dose and timing
Doses used in the research on file, taken as 1 dose. Not a recommendation.
Logarithmic time scale. Individual metabolism varies.
Safety and interactions
| Recorded side effect | How often | Severity |
|---|---|---|
| Morning grogginess (high dose) | common | mild |
| Vivid dreams | common | mild |
Side effects in detailRecorded interactionsInteraction checker
History
Aaron Lerner isolated melatonin from bovine pineal glands at Yale in 1958, and Russel Reiter and others characterised its circadian role. A Cochrane review by Herxheimer[1] assessed it for jet lag, and Zhdanova 2001 studied a 0.3 mg dose.
References
- Melatonin for the prevention and treatment of jet lag (Cochrane review by Herxheimer). 2002. PubMed 12076414
Reader reviews
0 publishedNo reader reviews have been published for this substance yet.
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Sign in to reviewMelatonin: quick answers
- How strong is the evidence for Melatonin?
- The overall grade on file is A (strong). 3 claimed benefits are graded separately in the table above. 2 of the benefit grades of A have no verified study cited yet. The entry cites 1 study.
- What dose of Melatonin has been studied?
- The range on file is 0.3-3 mg (1 dose). It describes doses used in research, not a recommendation.
- How long does Melatonin take to work and how long does it last?
- Listed onset: about 30 minutes. Listed half-life: about 1 hour. Individual metabolism varies.
- What are the side effects of Melatonin?
- Recorded side effects: Morning grogginess (high dose) (common), Vivid dreams (common). Safety score 5/5.
Compared with other substances
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